Process for cleaning valve in crankcase ventilating system and cleaning composition



United States Patent 3,476,091 PROCESS FOR CLEANING VALVE IN CRANK- CASE VENTILATING SYSTEM AND CLEAN- ING COMPOSITION Robert E. Malec, Birmingham, Mich., assignor, by mesne assignments, to Armour Industrial Chemical Company, a corporation of Delaware No Drawing. Filed Sept. 22, 1966, Ser. No. 581,146 Int. Cl. F01m 3/02; Cm 1/20 US. Cl. 123--1 4 Claims ABSTRACT OF THE DISCLOSURE A non-symmetrical ketone is admixed with motor oil whereby, upon use, the ketone volatilizes and then deposits on parts of the motor to dissolve gums and sludges.

This invention relates to a cleaning technique and composition for positive crankcase ventilation systems and more particularly to an additive comprising a nonsymrnetrical ketone, which, when admixed with motor oil, sufficiently volatilizes during use and then deposits on the cooler positive ventilator system of the crankcase and there dissolves gum and sludge which tend to build up at such location. By so doing, the system continues to operate thereby insuring smog-free operation.

With the advent of smog-control devices, in particular, positive crankcase ventilator systems, a new problem has arisen. The system which utilizes a valve that closes and then opens after the engine is started, tends to build up gum and sludge. It is imperative that the valve be kept clean to assure continued operation. A stuck valve immediately stops the smog-control system.

Two approaches have been considered, but none have accomplished the desired level of success. One approach involved the use of detergent-containing motor oil, while the other involved the use of high detergency gasoline. Both are expensive and both do not satisfactorily remove the gum and sludge so that continued operation of the positive crankcase ventilation system is not assured.

An object of this invention is to provide a novel technique for keeping clean and for cleaning the positive crankcase ventilation system of vehicles.

Another object is to provide a motor oil additive which keeps clean and cleans positive crankcase ventilation systems.

Still another object is to provide a technique and an additive of the above character which is efiicient.

A further object is to provide a motor oil additive which is automatic in its cleaning operation of the positive crankcase ventilation system.

A still further object is to provide an additive of the above character which has good solvency for the gum and sludge which build up in the positive crankcase ventilation system.

Another object is to provide an additive of the above character which is compatible with motor oils.

Another object is to provide an additive which volatilizes at the temperature normally encountered by motor oils during operation.

Another object is to provide an additive which has controlled volatility whereby adaptability and efficient use of particular motor oils is possible.

Other objects of the invention will be part be obvious and will in part appear hereinafter.

It has now been found that unsymmetrical aliphatic and aryl methyl ketones, when added to motor oils, automatically volatilize to an extent at the temperatures normally encountered during operation of the motor, and deposit upon the cooler parts, such as the positive crankcase ventilator system, where they dissolve the gum and sludge that normally deposit there and flow back into the motor oil where they are consumed by combustion or removed by filtration. More particularly, it has been found that ketones falling within the following formula:

Formula I 0 Bike where R is a member of the group consisting of unbranched and branched alkyl radicals of C to C carbon atoms, cycloalkyl radicals of C to C carbon atoms, aryl radicals and alkylaryl radicals with the alkyl chain of said alkylaryl radical having the scope of alkyl radicals above; R is a methyl radical, and when the above comprises at least a major portion (60% and above) of the ketone utilized, balance is a ketone also of the above formula where R-+R'=C to C alkyl radicals; when added to motor oil in a concentration of 0.5% to l0% by wt., effect a unique vaporous solvent cleaning action on the auxiliary accessories of the motor, such as the positive crankcase ventilator system, whereby said accessories will have trouble-free operation.

The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others thereof, and a composition of matter possessing the characteristics, properties, and the relation of components which will be exemplified in the composition hereinafter described, and the scope of the invention will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed examples:

Example I TABLE 1 Carbon tetrachloride soluble Insoluble Test deposits, deposits No. Oil mg. mg

1 SAE 30 premium 147. 1 22. 7 2 SAE 30 premium plus 1% methyl heptyl ketone plus 1% methyl nonyl ketone. 98. 2 3. 6

3 Example II Another series of tests are run in the field as follows:

tive crankcase ventilation system, particularly the valve associated therewith positioned between the crankcase TABLE 2 PCV valve Initial Final deposits Automobile Additive Motor Oil mileage mileage (mg.

1963 Dodge V-S 2% crude methyl coco ketone Quaker State HD L-.. 19, 080 21, 020 None 1964 Pontiac V-8 do Shell X400 2 17, 410 20,600 172 1963 Dodge V-8 2% methyl nonyl ketone 21,020 None 1964 Pontiac V-8 None Shell X-100 20, 600 29, 500 536 1 Manufactured by Pennsylvania Oil Co., Philadelphia, Pa.

1 Manufactured by Shell Oil of Emeryville, Calif.

It might be noted that ketones have several advantageous properties which make those of Formula I even more unique for the use described. Generally, ketones are thermally, oxidatively and hydrolytically stable. They are unreactive toward and stable with all the commonly used types of motor oil additives so that they may be utilized along with such other additives. And, they are, at least those of Formula 1, compatible with oil so that solubility is no problem.

The ketones may be added to any motor oil, including those of the detergent and the non-detergent types. Usually 0.5% to 1 by wt., and preferably 3% is needed to accomplish the objectives of this invention.

In selecting a specific ketone, or mixture of ketones, care should be taken to select those that have the desired amount of volatility under the use condition they will encounter. In other words, it is preferable to determine the normal operating temperature of the motor and then select one or a combination of ketones falling within Formula I above, which volatilize to a degree at such operating temperatures. With such volatilization-condensation cycle, any deposits that are formed on the PCV will be kept flowing either in solution with the ketone or else as a body floating within the ketone.

The ketones may be premixed with motor oil or else added directly to the crankcase.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in carrying out the above method and in the composition of matter without departing from the scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention, which, as a matter of language, might be said to fall therebetween.

Now that the invention has been described, what is claimed is:

1. A method for cleaning and keeping clean the posivent and the intake to an internal combustion engine comprising utilizing in the motor oil 0.5 to 10% by weight of at least one ketone falling within the following formula:

0 R-g-R' where R is a member of the group consisting of unbranched and branched alkyl radicals of C to C carbon atoms, cycloalkyl radicals of C to C carbon atoms, aryl radicals and alkylaryl radicals with the alkyl chain of said alkylaryl radical having the scope of alkyl radicals above; R is a methyl radical; and when the above comprises at least a major portion of the ketone utilized, the balance is a ketone where R+R'=C to C alkyl radicals; in the crankcase system, the particular ketone selected being one which volatilizes under the normal operating condition of said engine and, volatilizing said ketone which is conveyed to said ventilation system and said valve.

2. The method of claim 1 wherein said ketone comprises methyl heptyl ketone.

3. The method of claim 1 wherein said ketone comprises methyl nonyl ketone.

4. The method of claim 1 wherein said ketone comprises methyl coco ketone.

References Cited UNITED STATES PATENTS 2,096,678 10/1937 Fawcett 203-459 XR 2,129,596 9/1938 Waterman et al. 203-89 XR 2,165,261 7/1939 Hewlett et al 25252 XR 2,221,380 11/1940 Horsch 25252 2,620,306 12/1952 Stewart et al. 25252 3,173,408 3/1965 Brenneman 123119 3,405,065 10/1968 Goodwine 252-51.5

DANIEL E. WYMAN, Primary Examiner W. CANNON, Assistant Examiner US. Cl. X.R. 1231l9; 25252 

